Stringed musical instruments such as guitars, basses, violins and cellos typically include a neck coupled to a body at a neck joint and strings strung between the neck and the body. The body may take various shapes depending on the desired acoustic and structural characteristics. For example, acoustic instruments generally include hollow bodies, while electric instruments oftentimes include solid or semi-solid bodies that provide support for various electronics, still further some instruments may be hybrid acoustic and electric and may have solid and hollow body portions.
The neck is generally a narrow elongate member. That configuration results from the functional requirements of the neck. For example, the neck must be long enough to suspend the strings over a significant distance. In addition, the circumference of the neck must be sized so that a musician is able to wrap their hand at least partially around the neck to manipulate the strings. Because of the configuration, necks are often susceptible to warping and disfiguring both during manufacture and over time. As a result, it is desirable to include a neck joint that is adjustable or allows the neck to be replaced.
Various attempts have been made to provide a neck joint for a stringed musical instrument that may be adjusted and/or disassembled. For example, U.S. Pat. No. 2,497,116 to Dopyera teaches a musical instrument, such as a guitar, having a neck attached to a body. Specifically, the neck portion includes an extension that protrudes perpendicularly from the neck into a well included in the body. A pair of fasteners is provided that couple the extension to the body and adjust the angle of the neck with respect to the body by manipulating the position of the extension within the well.
Such a system presents multiple disadvantages. One drawback is that the attachment between the neck and body portions requires the use of more than a single fastener. Another drawback of the system is that both fasteners are oriented substantially parallel to the guitar soundboard. Because of that orientation, it is difficult and problematic to insert the screws through the sidewall of the guitar, particularly since the screw holes are disposed directly underneath the neck. In addition adjustment of the screws is cumbersome. Furthermore, such an arrangement alters the aesthetics of the guitar.
In another example, shown in U.S. Pat. No. 5,886,272 to Regenberg, a neck joint is formed between a protruding trapezoidal heel of a neck that extends into a matching trapezoidal pocket in a guitar body. The close fit of the trapezoidal pocket and heel in addition to the walls of the pocket on every side of the heel limit movement of the heel. A plurality of fasteners secures the neck to the body.
A drawback of the guitar is that entire surfaces of the heel and/or the pocket must be carefully shaped and held to tight tolerances to achieve a desired fit which significantly increases the effort required to produce a proper fit. In addition, because it is difficult to achieve such a fit between the trapezoidal parts it is likely that multiple fasteners would be required to allow the use of looser tolerances. In fact that reference even recognizes that the length of the pocket should be as long as possible to reduce possible alignment error. However, such a requirement may have a direct deleterious effect on the aesthetics and structure of the body because it requires the engagement between the neck and body to be as long as possible to improve the fit.
In view of the above, there exists a need for a musical instrument featuring an uncomplicated and easy to manufacture adjustable attachment between the neck and body portions that creates a reliable fit.